It is known to implant medical devices such as stents, stent-grafts, vena cava filters, and so forth, into body lumens, such as arteries to reinforce, support, repair or otherwise enhance the blood flow through the lumen.
Stents are commonly used where an artery is blocked, or otherwise damaged. The stent, once in place, reinforces that portion of the artery allowing normal blood flow to occur through the artery. One type of stent that is popularly used for such purposes is a radial expandable stent. This is a tubular or cylindrical stent which can be radially expanded from a first smaller diameter to a second larger diameter. These stents are either self-expanding, or are pressure-expandable.
The stents are inserted into an artery through the use of a stent delivery device and are fed internally through the arterial pathways of the patient until the unexpanded stent is located where desired. The catheter may either be fitted with a balloon in the case of a pressure expandable stent, or with stent retaining sleeves in the case of a self-expanding device. These expandable stents have properties such that they remain expanded after the catheter has been removed.
In the use of radially expandable surgical stents, it is important to precisely determine the position of the stent, both before, during and after it is implanted and expanded. Stents are typically formed of metals or metal alloys including stainless steel, shape memory alloys, such as nickel-titanium alloys, or some other such alloy which in and of themselves are not readily visible using fluoroscopic imaging techniques.
To achieve precise positioning, stents have been paired with image markers to visualize the stent during the time that they are being deployed and also after they have been deployed, at periodic time intervals. Various attempts have been made to attach markers to stents, such that marker is carried by the stent.
Methods of attaching radiopaque material to medical devices through various mechanical and bonding techniques have previously been disclosed. Examples of such methods may be found in U.S. Pat. No. 5,741,327, U.S. Pat. No. 6,022,374, U.S. Pat. No. 6,334,871, U.S. Pat. No. 6,503,271, and U.S. Pat. No. 6,464,720. Prior methods can have various limitations. Among other things, through various prior attaching methods, the resulting stents have burs, weld markings and/or deformation markings on the marker or the stent. Prior methods can also be tedious in the attachment to the stent resulting in decreased efficiency in production, and they can also be difficult to attach in a precise location. There continues to be a need in the art for new and improved radiopaque markers for use on radially expandable stents which can be utilized on stents of all different sizes and provide clear images on a fluoroscope or other medical imaging device. Furthermore, there remains a need in the art for a simple method of fabrication for such radiopaque stents.
All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
A brief abstract of the technical disclosure in the specification is provided as well only for the purposes of complying with 37 C.F.R. 1.72. The abstract is not intended to be used for interpreting the scope of the claims.